1. Field of the Invention
This invention relates to a color pick up tube for use in color television camera devices, in particular to the target structure of a pick up tube used for producing a plurality of color components.
2. Description of the Prior Art
Color television cameras of the single pickup tube type have been proposed utilizing a series of different optical filter strips in a recurring sequence in order to separate the light from a subject image into its color components as imaged upon the pickup tube target.
In this type of color pickup tube, the target structure comprises a transparent substrate or face plate, a plurality of red, green and blue optical filter strips disposed thereon and interleaved in a predetermined sequence, a plurality of optically transparent, electrically conductive strips corresponding to each of the filter strips, a thin glass layer inserted between the optical filter strips and the electrically conductive strips, a substantially continuous layer of photoconductive material covering the conductive strips, and leads or bus bars interconnecting the conductive strips of like color response.
In the above target structure, it is necessary to interpose the thin transparent glass layer between the optical filter strips and the conductive strips (or electrodes) for the manufacture and effective operation of the color pickup tube.
However, including the thin glass layer, poses a serious problem that is a optical color cross talk or undesirable color mixing for the reason given later. This problem has been solved by use of an expensive optical lens system or complicated circuit arrangements in conventional color pickup tubes.